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Fuel System: Precaution

CAUTION:
  • Before working on the fuel system, disconnect the cable from the negative (-) battery terminal.
  • Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
  • Do not smoke or work near an open flame when handling the fuel system.
  • Keep gasoline away from rubber or leather parts.
  • Do not allow fuel to spray when removing the pipe between the high pressure side fuel pump and the fuel injector. The fuel in the pipe is highly pressurized.
  1. DISCHARGE FUEL SYSTEM PRESSURE 
    CAUTION:
    • Do not disconnect any parts of the fuel system until you have discharged the fuel system pressure.
    • Even after discharging the fuel pressure, place a piece of cloth or equivalent over fittings as you separate them to reduce the risk of fuel spraying on yourself or in the engine compartment.
    • Allow the engine to cool down before performing the following procedures, as the high pressure side fuel pressure does not decrease until the engine cools down.
    NOTE: Perform these procedures with the engine coolant temperature at 60°C (140°F) or less.
    1. When removing the F/PMP relay
      1. Remove the No 2 relay block cover UPR
      2. Remove the F/PMP relay.
      3. Disconnect the fuel pump resistor connector (See REMOVAL  ).
      4. Start the engine
      5. After the engine has stopped, turn the engine switch off.

        HINT

        DTC P0171/25 (fuel problem) and/or P0191/49 (fuel pressure sensor signal error) may be detected

      6. Crank the engine again. Check that the engine does not start.
      7. Remove the fuel tank cap to discharge pressure from the fuel tank.
      8. Disconnect the cable from the negative (-) battery terminal
      9. Reinstall the F/PMP relay.
      10. Connect the fuel pump resistor connector
      Fig 1: Identifying F/PMP Relay
      G05749897Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When disconnecting the fuel pump connector.
      1. Remove the rear seat cushion assembly.
      2. Remove the rear floor service hole cover.
      3. Disconnect the fuel pump connector
      4. Start the engine
      5. After the engine has stopped, turn the engine switch off.

        HINT

        DTC P0171/25 (fuel problem) and/or P0191/49 (fuel pressure sensor signal error) may be detected

      6. Crank the engine again Check that the engine does not start
      7. Remove the fuel tank cap to discharge pressure from the fuel tank.
      8. Disconnect the cable from the negative (-) battery terminal.
      9. Reconnect the fuel pump connector
      10. Install the rear floor service hole cover.
      11. Install the rear seat cushion assembly.
        12. Fig 2: Locating Fuel Pump Connector
        G05749898Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. FUEL LINE 
    1. When disconnecting a fuel line, fuel will spray out. Observe the following procedure:
      1. Put a container under the connections
      2. Disconnect the fuel tube
      3. Drain the fuel remaining inside the fuel tube into the container
      4. Cover the disconnected fuel tube (fuel tube joint and fuel tube connector) with a plastic bag to prevent damage and intrusion of foreign matter.
        5. Fig 3: Identifying Fuel Tank Main Tube With Plastic Bag
        G05639795Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Observe the following procedure when disconnecting a fuel tube connector (quick type A).
      1. For fuel pipe clamp type A.

        Remove the No 1 fuel pipe clamp

        Fig 4: Locating Fuel Pipe Clamp
        G04947837Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. For fuel hose connector cover type A:

        Remove the fuel hose connector cover

        Fig 5: Locating Fuel Hose Connector Cover
        G05749901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. For fuel hose connector cover type B:

        Disengage the lock claw by raising the fuel hose connector cover as shown in the illustration.

      4. Check for foreign matter on the pipe and around the connector before disconnecting it. Clean it if necessary.
        Fig 6: Identifying Fuel Hose Connector Cover
        G05639797Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. If the connector and pipe are stuck, pinch the connector, and push and pull on the pipe to disconnect them.
        NOTE: Do not use any tools in this step.
        Fig 7: Removing Fuel Pump Connector
        G05387477Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Check for foreign matter on the seal surface on the disconnected pipe Clean it if necessary.
      7. To protect the disconnected pipe and connector from damage and foreign matter, cover them with a plastic bag.
      Fig 8: Identifying Disconnected Pipe And Connector With Plastic Bag
      G05639799Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Observe the following procedure when connecting a fuel tube connector (quick type A).
      1. Check that there is no damage or foreign matter on the pipe connections.
      2. Align the axis of the connector with the axis of the pipe Push the pipe into the connector until the connector makes a "click" sound. If the pipe is difficult to push into the connector, apply a small amount of clean engine oil to the tip of the pipe and reinsert it
        Fig 9: Pushing Pipe Into Connector
        G04947841Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. After connecting, check that the pipe and connector are securely connected by pulling on them
        Fig 10: Checking Proper Connection Of Pipe And Connector
        G04947842Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. For fuel hose connector cover type A:

        Install the fuel hose connector cover.

        Fig 11: Locating Fuel Hose Connector Cover
        G05749907Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. For fuel hose connector cover type B:

        Engage the lock claws to the connector by pushing down on the fuel hose connector cover.

        Fig 12: Pushing Down On Fuel Hose Connector Cover
        G05749908Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. For fuel pipe clamp type A.

        Install the No. 1 fuel pipe clamp.

      Fig 13: Locating Fuel Pipe Clamp
      G04947837Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Observe the following procedure when disconnecting a fuel tube connector (quick type B).
      1. Before disconnecting a connector, clean off any dirt that may be present.
      2. Pinch the tabs of the fuel tube retainer to disengage the 2 claws. Push the retainer down as shown in the illustration.
        NOTE: Be sure to disconnect the connector by hand.
        Fig 14: Pinching Tabs Of Fuel Tube Retainer
        G05639804Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. If the connector and pipe are stuck, hold the fuel pipe by hand and push and pull on the connector. Pull the two pipes apart to separate the connector.
      4. If there are any dirt or any other foreign matter on the sealing surfaces of the disconnected pipes, clean them if necessary
        Fig 15: Pushing And Pulling On Connector
        G05639805Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Do not damage the disconnected pipe and connector, and prevent entry of foreign matter by covering them with plastic bags.
      Fig 16: Covering Disconnected Pipe And Connector With Plastic Bags
      G04947845Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Observe the following procedure when connecting a fuel tube connector (quick type B).
      1. Line up the two parts of the pipes to be connected, and fully push the fuel tube connector and pipe together until they are fully seated Push the retainer into the connector until its claws lock If the pipe is difficult to push into the connector, apply a small amount of clean engine oil to the tip of the pipe and reinsert it
      2. After connecting, check that the pipe and connector are securely connected by pulling on them.
      3. Check for fuel leaks.
      Fig 17: Pushing Fuel Tube Connector And Pipe
      G05639807Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Observe the following precautions when handling a nylon tube:
    CAUTION:
    • Do not twist the connection part of the nylon tube or the quick connector when connecting them.
    • Do not bend or twist the nylon tube.
    • Do not remove the EPDM protector on the outside of the nylon tube.
    • Do not pinch or kink the nylon tubes to prevent fuel leaks.
  3. INJECTOR 
    1. Observe the following precautions when removing and installing fuel injectors:
      1. Do not reuse a O-ring
      2. When placing a new O-ring onto the injector, do not damage the O-ring.
      3. Coat a new O-ring with gasoline before installing it Do not use engine oil, gear oil or brake fluid
      Fig 18: Identifying Correct And Incorrect Position Of Injector
      G04974986Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Install the injector into the delivery pipe and cylinder head as shown in the illustration. Apply gasoline to the contact surfaces of the delivery pipe and the injector before installing the injector.
    Fig 19: Identifying Injector, Delivery Pipe, Insulator And Intake Air Surge Tank Assembly
    G05749915Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. FUEL SUCTION TUBE ASSEMBLY WITH PUMP AND GAUGE 
    1. Do not disconnect the tube shown in the illustration when disassembling the fuel suction tube assembly with pump and gauge. Doing so will cause reassembly of the fuel suction tube assembly with pump and gauge to be impossible as the tube is welded to the plate.
    Fig 20: Identifying Fuel Suction Tube Assembly
    G05749916Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT FOR FUEL LEAK 
    1. Check that there is no fuel leakage after performing maintenance anywhere on the fuel system (See ON-VEHICLE INSPECTION ).
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